Influence of the film deposition rate and humidity on the properties of thin CsI photocathodes

Optical and photoemissive properties of CsI photocathodes (PCs) grown at two different evaporation rates (1 and 0.04 nm/s) have been investigated. rface morphology of 300-nm-thick CsI films was also studied by means of atomic force microscopy. After 24-h exposure to humid air, properties of PCs grown at the slowest evaporation rate resulted affected more than those obtained at the fastest rate, making this latter more adequate for the photocathode preparation.